Scanning White Light Interferometry (SWLI), also known as vertical scanning or coherence radar, takes advantage of the fringe localization in low-coherence interferometers to profile complex surface shapes. Combining phase and coherence information for improved precision requires dedicated algorithms for dealing with possible inconsistencies between these two measurement techniques. See, for example, “Determination of Fringe Order in White-Light Interference Microscopy”, Peter de Groot, Xavier Colonna de Lega, Jim Kramer, Michael Turzhitsky, Applied Optics, Volume 41, Issue 22, 4571–4578, August 2002. Some of these inconsistencies are due to geometric and chromatic aberrations that are typical of optical components. Those same aberrations are also responsible for reducing the effective lateral resolution of these profilers.